Machine for forming gears



May 3, 1949.

Filed May 51, 1946 H. PELPHREY ET AL 2,469,310

MACHINE FOR FORMING GEARS l3 Sheets-Sheet l INVENTORj Harry EZ vZ/e y,

y 1949- H. PELPHREY ET AL 2,469,310

MACHINE FOR FORMING GEARS Filed May 51, 1946 1s Sheets-Sheet 2 h 7 ill/VENTURE E )ik f/z May 3, 1949.

I MACHINE FOR FORMING GEARS Filed May 31, 1946 13 Shets-Sheec 5 7' .5 ZIP: f Y

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NVENTOR5, fidrf 79/ Z455 May- 3, 1949.

Filed May 51, 1,946

H. PELPHREY ET AL MACHINE FOR FORMING GEARS 13 Sheets-Sheet 4 EAL-- fro/wring y 3, 1949- I H. PELPHREY ET AL 2,469,310

MACHINE FOR FORMING GEARS Filed May 31, 1946 13 Sheets-Sheet 5 IN V EN TOR5.

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May 3, 1949.

Filed May 31, 1946 H. PELPHREY ET AL 2,

MACHINE FOR FORMING GEARS 15 Sheets-Sheet 6 INVENTORS.

y 1949- H. PELPHREY ET AL MACHINE FOR FORMING GEARS l3 Sheets-Sheet 7 Filed May 31, 1946 W T. N m m y 1949. H. PELPHREY ET AL 0 MACHINE FOR FORMING GEARS Filed May 31, 1,946 13 Sheets-Sheet 8 May 3, 1949. H. PELPHREY ET AL 2,469,310

MACHINE FOR FORMING GEARS Filed May 51, 1946 l3 Sheets-Sheet 9 May 3, 1949. H. PELPHREY ET AL MACHINE FOR FORMING GEARS l5 Sheets-Sheet 10 Filed May 31, 1946 MwN 7 ZINZENTORfi.

y 1949- H. PELFHREY ET AL 2,469,310

MACHINE FOR FORMING GEARS Filed May 51, 1946 13 Shets-Sheet 11 15 Sheets-Shet 12 H. PELPHREY ET AL MACHINE FOR FORMING GEARS NWM May 3, 1949.

Filed May 51, 1.946

ay 1949- H. PELPHREY ET AL 2,469,310

' 'MACHINE FOR FORMING GEARS Filed May 31, 3.946 I 13 Sheets-Sheet 13 352 v INVENTORfi,

Harry PQZ IZfeg,

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Patented May 3, 1949 UNITED STATES MACHINE FOR FORMING GEARS Harry Pelphrey,'l)etroit, and James Martin, Ferndale,- Mich, assignors to MichiganTqol-pompany, Detroit, Mich, a corporation of Delawai-e Application May 31-, 1946,SerialNii:3613

17 Claims.

The present inventionvrelatestoa machine for forming gears, and -has more particular relation to a machine for: simultaneously formingv all the teeth on a gear blank.

As is well known; it is converitional practice to form gears on a-gear 'blankbymeans of a gear shaper, or to generate the same in a generating action between a-hob an-d the gear blank. While it is possible to produce satisfactory gears by either of these methods, each is inherently slow, inasmuch as in; either processthegear teeth are individually formed; Itwill be obvious; therefore, that the time consumed inproducing agear by either of the above methods is of importance even in the case of-a gear with relatively few teeth, and will beincreasingly more important in the case of gearshaving a substantial number of teeth.

In United States Letters Patent 2,346,867 to Harry Pelphrey; zwhich patent isassigned to the assignee of this-application, a machine for forming gears by'which' all of theteeth in the gear may be-simultaneously formed'on a gearblank is-fully 'describedand illustrated.

The present invention -lalthough somewhat similar to the said Pelphrey'patent, has been greatly improved and provides, among other things, novel and improved means for-preventing interference between the-cuttingtools and a gear blank when forming" :a helicalgear;

Consequently, theprimary object of the present invention is to provide a machine for simultaneously formingall the teeth ona gear with which it is possible to form such teeth on a helical gear without interference between the cutting tools and the flanks of the teeth as the same are-being formed.

Another objectofthis invention is to provide a construction with which it-is possible to thus simultaneously formrall the-teeth of a helical gear without interference between the cutting tools and the flanks-of the-gear teeth by causing the cutting tools to contact thegear blank along a constant helical path for a predetermined part of the gear forming "cycle, To accomplish this,- means are provided to decrease the spiralangle which the gear blank follows as-it reciprocates.

A further object oflthepresentinvention is to provide a machine for thus forminggears which is substantially automatic in operation.

A still further object of the. present invention is to provide a machinezforsimultaneously forming all theteeth on a gear which may be operated by semiskilled or relatively unskilled labor to produce: extremely accurate gears.

Further objects andaadvantages o'f our in-Ven tion will be -apparent from::the"description which follows when considered in c'onnection iwith the accompanying-:dr'awingaf in which"likenumerals= indicate like parts wherever showmand wherein? Figure l is=a perspectlve viewpr agear form-- ing machine for simultaneously forming v-all the teeth of -a---gea-r,' which machinefiembodies the improvements ofi'the' present inverition.

Figure 2 is a perspective view of a part'ot-the left side of the machine of Figure 1' with- 'an accessdoonremovedto illustrate certain of the apparatus located: interiorly of: the basei Figure'3 is-a sectionalaelevatiozr' oft the left side' of the machineyillustratingthatportion of" 1ine1 55 of"Figure-Sshowingth apparatusfor" decreasing thespiral anglewhich the gearblank follows during partofi the gear' f orm'ing cyc'lei Figure '6 'is a' sectionta'ken-:on 'line ii-=6 of Figure 5 to show the-driving mechanism interiorly of the base.

Figure -7 is' a view taken substantially ron line l---! of Figure 5 showing, dud-plan; the: apparatusfor decreasingcthehelix rotativemovement of the gear blank;

Figure 8 is a sectio'n taken: online '8-----8 of Figure 4- illustrating the apparatus fori efiecting reciprocation-ofvthe tool-holder:

Figure '9' is a section: on lined-=9 "ofl igure 8, illustrating oneof: the lock bars :for retaining the tool-head; duringrreciprocation of thetool holder.

Figure 10 is a sectionon line -'l0-l0 of-Figure 9, showing theadiustment means -for the-loclebaru Figure 11 is aview taken in the 'directionof arrow 1 I: shown in Figure? 4;--illustrating-:the: ap-- paratus -f or vertically shifting the head stop;

Figure 12'is a section'on line--l-2-l*2 of Figure 11'.

Figure l3-is asection an line lit-43 of Figure-8, illustrating the blade adjustment :mechanis'm.

Figure 14 is an enlarged: view of theram and spiral guides show-nimFigure'll Figure -15 is 'a section taken substantially :on line I 5-l 5- oi'Figure "-4; showing the toorhc-lder reciprocating camsand 'the ratchet for driving the: tool advancement cam:-

Figure 16' is a diagrammatie sketch of= why-' draulic system which may be used to operate the gear forming machine of this invention.

Figure 17 is an enlarged view of the apparatus included in circle I! on Figure 7.

Figure 18 is a sectional view similar to Figure 7 illustrating a modified form of the variable guide mechanism.

Figure 19 is a section similar to that illustrated in Figure 15, showing the apparatus for diminishing helical rotation of the gear blank, driven by the ratchet for advancing the cutting tools, in the modified form of the invention. I

Figure 20 is a view taken in the direction of arrow 20 in Figure 19.

In the present invention, a construction is provided in which a plurality of circumferentially spaced, radially disposed cutters are mounted in a tool head in surrounding relationship to a gear blank. Such gear blank is mounted upon a reciprocating work holderand upon upward movement of such work holder, the gear blank is moved into cutting engagement with the cutters. These cutting tools are alternately fed radially inwardly and backed offduring reciprocation of the work holder so that as the cutters are fed inwardly, all of the gear teeth are formed simultaneously. The cutters are of such shape that in the complete operation they remove entirely the interdental stock between the teeth formed thereby.

Although the specific embodiment of the invention herein described and illustrated is particularly applicable to forming helical gears, it will be obvious that a machine embodying the improvements of the present invention may be used to form other types of gears.

In order to thus simultaneously form the teeth on the helical gear, the present invention contemplates mounting the cutters at an angle to the axis of reciprocation of the machine element or gear blank. Such gear blank is partially rotated with respect to its longitudinal axis as it is reciprocated by the work holder. To effect this rotation, a reciprocating ram upon which the work holder is mounted is caused to rotate upon the helix of the gear to be'cut. It will be appreciated, however, that the angular setting of the cutting tools with respect to the axis of reciprocation must correspond to the helix angle at the outside diameter of the gear to be formed. Obviously, as the cutting tool moves more deeply into the work piece, this helix angle must decrease as it is a function of the radius. The present invention contemplates providing apparatus for decreasing the helical rotative movement of work holder effected by the helical guides through part of the forming operation to prevent interference between the cutting tools and the flanks of the teeth being formed on the gear blank. The compensating action effected by this guide is greatest at the outer diameter of the gear blank, gradually diminishing as the radially disposed cutting tools approach the base of the gear teeth. As the tools reach a predetermined point in this inward travel, such action ceases and a locking means enters the ram guide housing, causing the gear blank to be rotated in accordance to the helical path of the gear to be formed thereon for the balance of'the operation.-

To fully describe the machine of this invention, it is necessary to refer to the drawings in which a base is generally indicated at I Such base may be an integral, hollow casting suitably reinforced and providing doors through which access may be had to the-mechanism located interiorly thereof. In order to provide for mounting the work holder and reciprocating means therefore, this base provides in the lower portion, annular opening 2 with surrounding boss 3. A locating ring 4 is integrally connected to the top of said boss by bolt 5 and provides annular wall 6 extending downwardly in such openin 2. At the right side of this locating ring 6, as may be seen in Fig. 5, is provided an adjusting stud i and lock nut 8. This stud and lock nut provide for a slight, lateral shifting of the locating ring upon said boss 3. It will be observed that the extent of this lateral shifting is limited to the clearance provided between bolt 5 and locating ring 4 at the point at which said bolt extends through the opening provided therefore in the ring.

A ram guide housing 9 is disposed within the annular opening provided by annular Wall 6 to depend downwardly by means of shoulder portion I!) from the upper surface of the locating ring 4. As will hereinafter become more clear, this guide housing may be rotated about its longitudinal axis, and for this reason shoulder H1 thereof is secured to said surface of ring t by means of shoulder cap II which permits such rotation. This shoulder cap I I is in turn secured to the locating ring 4 by means of bolt l2, one of which is shown in Fig. 5.

At the top of the guide housing 9, the ram guide i3 is integrally connected thereto for slidably receiving ram extension l4 which is fixed to the top of ram [5 by means of bolts it. A work holder H is rigidly connected to the upper extremity of said ram extension M by bolt l8, and provides for clampingly receiving and holding therein the gear blank f9 in a manner to be hereinafter described.

In order to prevent chips from entering the gear forming apparatus, a chip deflector 2B is anchored to the base of work holder I! for reciprocation therewith. Such chip deflector provides interiorly thereof a downwardly directed portion 2! which is adapted to receive cylindrical guard 22 fixed to the outer diameter of ram guide l3. In this manner, such gear forming machine is protected from chips during the reciprocation of the Work holder.

In the lower portion of the guide housing, ram swivel connection 23 is slidably disposed. At the bottom end of ram l5, thrust bearing 24 is anchored thereto by means of lock nut 25 which threadably engages a threaded end of ram l5, and thus held to the ram. This thrust bearing is received within swivel connection 23. An end plate 26, anchored at the top of swivel 23, abuts the upper surface of bearing 24 to rigidly secure the same to the swivel. This swivel connection 23 provides mating openings through which crank pin 21 passes to hold the crank 29 within opening 28 of said swivel.

With the work holder thus integrated to the crank 29. reciprocation thereof is accomplished in the following manner. A prime mover in the form of an electric motor 30 (Figure 16) drives suitable gearing in gear box 3! to drive clutch 32 and through such clutch, shaft33. This shaft 33 drives worm 34 to drive worm gear 35 fixed to shaft 36, overlying and perpendicular to said shaft. A gear 31, secured to shaft 36, meshes gear 38 on shaft 39 of which gear 40 is an integral part. Such gear 40 in turn meshes gear 4| keyed to crankshaft 42 for driving the crankshaft. It will be observed that crankshaft 42 is journaled for rotation upon suitable'bearings areas-r carried in the bearing housings-43, 44, an'd l5, respectively, and that such crankshaft provides an eccentric shoulder at 46. The --eccentric shoulder 45 is rotatably received within an opening provided in adjustable eccentricAl. This eccentric ring which is adjustable is received within bearing 48 provided in arm 29. Obviously, as crankshaft 42 is caused to rotate the-eccentricity of shoulder 46 will efiect crank 29 to reciprocate causing the Work holder to reciprocate therewith.

As a means for varying the length-of the stroke of crank 29 to accommodate various gear widths, adjustable eccentric 4! has 'a gear portion "49 thereon. The face of. gear 149 abuts face of gear 50 which is secured by means 05 tapered 'pin '5l to the eccentric shoulderiflfi of crankshaft 42. It will be observed thereforathatwhile adjustable eccentric 41 may be rotatablyshifted about shoulder 45, gear 50 may not bermoved. An internally tooth gear .52 is disposed-Ito;meshithe teeth of both gears .49 and "50. Such internal gear 52 provides groove 53 extending aroundlthe periphery of such gear in WhiCh'thEZfiIlgBITBI of locator 55 is received. Thisilocator-155ris-anchored by means of bolt 56 togear 50, and it will be appreciated that linger 54 ifollowin groove 53 in th gear.52 will preventthissgear from leaving the teeth of its meshing. gears. By inserting a pin in one-of .the drill openings 51 found on the outer diameter of .gear 52, such gear may be rotated. As gear 52; is.-rotated:in this manner, gear 49 will rotate therewith,zcausing the adjustable eccentric ll to rotate about shoulder 45. Adjustment .of' eccentricd'lxby; such means, of course, changes the stroke of .cranki29 to accommodate various gear'widths.

As the ram l5, together withwork' holder H and gear blank 19 are reciprocated, it -is..also turned or rotated with respect to its longitudinal axis. This provision istmade .so thatany" point on the periphery of thegeanblank follows the path of the helix of the gear tobe formed-there- In order to effect such turning asecond guide means is disposed withinguide housing l3. .Such guide means include a spiral guide 58 which is fixed to the stem of ram extension'M. Such guide 58 has a spiral guide surface-59, which'ha's a contourfollowing the/helix of thegear. to: be formed on the gear blank. Complementary spiral guides 60 and SI" are fixedrto the. guide housing 9 by means of bolts: 62 and 63, respectively. The guides'fio and GI haveaspiralguide surface B l, which cooperates with the-,guide surface of guide 58 to properly-guide the ram as the same reciprocates andis rotated upon the-helix of the gear to be formed on-the :gear blank.

It will be appreciated that although the lead angle of a helical gearremainsnconstant, the helix angle of such type gear varies with the radius. That is to say, the-helixangle of. such type gear is less at the base: circle thereof than at the outer diameter. This variation in helix angle, it has been found, causes interference vbetween the cutting tools and. theflanks of the gear teeth beingformed on the gear blank when a helical gear is 'being'produced. The machine of this invention provides novel means forpreventing such interference.

In order to accomplish this desirable result, annular ring 65 is-secured-to: guide housing =9 by a plurality of bolts 66. As :may be seen; in Figures 5 and 7, ring-65gprovidesatthe -leit side,

.an integral lever-'61. 'Suchileversfl-noverlies.za

ternal. gear 85 keyed to said shaft.

a similar movement of pin 69.

providedttherefor in such lever arm El. This-pin ..69.is rotatably receivedvin slideblock 1B which is-slidably'positioned within slotll provided in pivot block 68. At'the lower end of pivot block :68, pivot 12 is machined thereon and thisis rotatablyireceivedwithin the bushing 73 carried .inLan opening provided in slide plate 14. A guide block 15, the shoulder '16 of "which engages -a shoulder portion 7'! of pivot block 153, permits suchblock'fill tomovezabout pivot l2,but preventsthe same from coming outv of the opening provided therefor. This slide plate 14 .is

tmounted to beslidably movedby cam 19 onmachine :surface 18 of .base I. :Said movement serves to move pivot l2 until the same is vertically below .pin 69, as will hereinafter become more clear.

Pivot block 68 also provides ,a U-shaped: slot in which theisma'll end of crank 8!: is adapted to register to be held therein by means of pin 82 vwhichextends through mating openings in such block and lever arm. The large end of crank rotatably receives adjustable eccentric 83. Such eccentric 83 is rotatably supported on shaft 34. The driving of shaft 84-forvefifecting rotation thereof is to be later explained in connection with the do-wnfeed slide mechanism.

vRotation of shaft 84 effects rotation of in- Such gear 85 is held by integral shoulder 86, from gear 87, which is also integral with such eccentric, in mesh With the teeth on gear 37 for driving the eccentric. It-will be appreciated then that as shaft '84 rotates, the eccentric -83 will rotate "therewith in timed relation thereto. centric 83 effects movement of crank SI, which This coin turn causes pivot block 68 to oscillate about pivot pin 12.

-With the pivot pin S2 in the position indicated inFigure 5, it will be observed that movement of crankrSI causes pivot block to move arcuately about pivot 12. Such arcuate movement effects However, it will be appreciated that inasmuch as pins 69 and 82 are on opposite sides of the pivot 12, each will .move oppositely. This movement of pin 59 is 50 imparted to lever Bl, eiiecting oscillation of guide housing 9 about its longitudinal axis, as such housing is fixed to ring '55 of which lever 59 is an integral part.

As such guide housing rotates in a direction opposite to that in which the arm is rotated by the spiral guides, the helix angle developedby .such rotation of the ram isreduced inasmuch as the guides 6i] and M fixed to the guide housing rotate therewith serving to cause guide 58 to fol- .low a reduced spiral angle. As will hereinafter become more clear, the extent of this counter rotation decreases as the cutting tools approach .tive movement thereof returns the mechanism in readiness for the next counter rotative movement in timed relation to the next stroke of the ram.

Gradual diminishing of the oscillatorymovement of guide housing 9 is accomplished in the following manner. As crank 8| is moved by means of eccentric 83, pawl 89, pinned at 90 to ear 9I, projecting sidewardly from crank 8|, engages ratchet wheel 92. A spring 93, attached to one end of ratchet 89 and to crank 8I, insures constant engagement between the pawl 89 and said ratchet wheel 92. Thus, as said crank 8| moves in one direction, it efiects rotation of ratchet Wheel 92 by means of pawl 89. A second pawl 94, pivotally supported at 95 upon arm 96 provided on base I, is held by means of spring 91 in engagement with the previously described ratchet wheel 92. This pawl prevents ratchet 92 from rotating in an opposite direction to that efiected by pawl 89. Such ratchet 92 is fixedly secured to shaft 98 which is journaled for rotation within housin 99 extending outwardly from base I. Also mounted upon shaft 98 for rotation therewith is the previously named cam I9. Such cam 79 is provided with shoulder I90 which brings said cam directly in line with cam follower IDI which is integral with slide plate 16. As the cam I9 rotates, it thereby moves plates I6 inwardly, carrying pivot block 63 with it until pivot point 12 is directly below the vertical center of pin 69. When this occurs, oscillation of lever 61 ceases, and hence oscillation of guide housing 9 also stops. At that instant, a limit switch I02 is contacted by button I03 on the lower end of shaft 98. This contact of the limit switch effects shifting of solenoid valve I94 permitting fluid to enter chamber I of the hydraulic cylinder I95. As the fluid enters this chamber, it forces piston I01 carried by such cylinder into opening I08 provided in guide housing 9 for preventing further rotation of said guide housing. This locking of the guide housing occurs at a predetermined point of the gear forming operation, depending upon the stroke of crank 8I which may be varied in accordance with the diameter of the gear being formed by adjusting the position of eccentric 83. After this locking action occurs, the balance of the forming operation is completed with the ram rotating by virtue of the spiral guides.

Positive engagement of follower IIlI on slide I5 and cam I9 is provided by springs I09 and I I0. Such springs are housed within openings provided therefor in the base I, to bear upon downwardly directed members III and H2 on slide plate I6, urging said follower on the slide plate against the cam.

In order to vary the movement of crank BI in accordance to the diameter of the gear to be formed, eccentric 83 is rotatably adjustable, which varies the stroke of such crank. To accomplish such adjusting rotation of eccentric 83, gear 85 is moved upwardly on shaft 84. This frees gear 81 from gear 85 and, of course, permits eccentric 83 to be rotated as a pin or other suitable means is inserted in the drilled opening 88 provided in the shoulder portion of such eccentric. Such adjustment of eccentric 83 changes the stroke of crank 8| to vary the extent of the oscillation of lever 61. Inasmuch as lever 61 is an integral part of annular ring I55, it will be appreciated that the oscillation of guide housing 9 will be effected. In this manner, such oscillation may be controlled in accordance with the radius of the gear being formed on such machine.

Thus, by means of reducing the helix angle at the line of contact between the cutting tools and the gear blank with the novel and improved means of this invention, it is possible to simultaneously form all the teeth on a helical gear 8 without interference to the'cutting tools and the gear blank,

In order to form the teeth in the gear blank I9 in the manner described, a plurality of circumferentially spaced, radially disposed cutters or tools II3 are mounted in a tool holder II4. This tool holder includes means for controllably feeding the tools II3' radially inwardly and backing oif such cutting tools with respect to the gear blank. Inasmuch as such cutting tools and cuttin head are similar to those described in the patent to Harry Pelphrey which has been previously mentioned in the foregoing, they will not be further described here. However, the machine of this invention provides novel and improved means for effecting reciprocation of the tools to effect such feeding and backofl of the same and such means will be described at this point."

A head assembly for mounting the cutting tools is provided in the upper portion of the machine. Such assembly which is generally indicated at H5 is mounted for slidable movement toward or away from gear blank I9 in order to provide for loading and unloading such gear blanks. To provide for such slidable movement, base I provides on the upper portion thereof machined surfaces at H6 and II! for thus mounting said head assembly II5. A gib is provided at H8 and keeper bars H9 and I2I] secure said head to the base.

To accomplish this sliding movement of head I I5, an integral hydraulic cylinder I2I is provided interiorly of said head. A ram I22 is anchored to the lower end of cylinder I2I. A shoulder portion I23, provided in ram I 22, receives annular cap I24 to close said end cylinder I2I when the ram is secured thereto. Closing of the upper opening in said cylinder I2I is accomplished by means of a cap member I25 anchored to said upper part of the cylinder. Within cylinder I2I, piston I26 is secured to shaft I21 which in turn is anchored to the upper part of base I. It will be appreciated, therefore, that as fluid is introduced into chamber I28 of the head, assembly II6 will be moved downwardly and, likewise, when fiuid is introduced into chamber I29 provided in said cylinder I22, the head will be effected to move upwardly.

As in United States Letters Patent 2,346,867 to Harry Pelphrey, previously noted above, the infeed and backoff movement of the cutting tools contained within previously mentioned tool head H3, is effected by means of an outer cone I30. This cone I 30 is anchored to the bottom of a sleeve member I3I for movement therewith. Such sleeve member I3I is disposed in surrounding relationship to ram I22 for reciprocation in a direction of the longitudinal axis of such ram by means of eccentric shafts I 32 and I33.

To provide for such reciprocation, carriage I34 is mounted within head II5 for independent movement in a direction parallel to the longitudinal axis of ram II4 as will hereinafter become more clear. Such carriage is gibbed at I35 to an appendage I36 of head H5 and secured to machine surfaces I31 and I39 of said head by means of keeper bars I39 and I40. An outwardly and rearwardly projecting portion I4I Which is integral with carriage I34 provides bearing hous ings I42 and I43, respectively, in which the previously described shafts I32 and I33 are journaled for rotation in suitable bearings. A shaft I44 is journaled for rotation in an overlying position with respectto shafts I 32 and I33 and normal thereto in bearing housing I45 which is integral with projection MI an bearing housing 'I46on bracket I41 anchored to said. projection 'I4I. Such shaft I44 rotatably supports cam I48-.- A rocker arm I49 is keyed to shaft I32 and double rocker arm I50 is keyed to shaft I33. A link II, pinned at I52 to rocker arm I50, and at I53 to rocker arm I49, effects simultaneous rotation of shafts I 32 and I33.- On the upper arm of double rocker I50, a rotatable follower I54 isseculed. Such follower I 54-is adaptedto be received within groove I55 provided on'cam I48, and it will thus be observed that as such cam rotates-the follower I54 will effect arm I50 to oscillate about its central point. Oscilation ofzarm I50will.be transmitted by means of the link I5I .toarm I49 serv ing to cause partial rotation of shaft I32 in a manner similar to the partial rotation of shaft I33.

Such rotationof shafts I32 and I33 effects rotation of eccentric shoulder I56 on'shaft I32 and eccentric shoulder I51 on shaft I33. Such eccentrics are journaled" for-rotation lll'blOCkS I58 and I59 respectively. Such bearing'block I5B'is received within groove I60 and, likewise, bearing block I59 is received within groove IEI, eachof which grooves is formed in the machined section I62 of sleeve I3I. Itwill be appreciated'that this'partial rotation of such eccentrics will effect a reciprocatory movementof sleeve I3I. lnase much as the outer cone I30 is secured to sleeve I3I, and the feed ring. I63 is in turn. secured. to the outericone, itican be seen that as thedepending end'I64 of such'feed' ring enters groove I65 provided in cutting tool I I2 such cutting tool will be moved inwardly on a down stroke. and:will, likewise, be backed off on-an up. stroke. Conside ering now that the means for accomplishingtthis reciprocation of'sleeve I3I is driven by the-driving means for effecting reciprocation of gear blank I9, as will later be described, it-is apparent that the infeed-and back-ofi of the cutting tools occur in timed relation to such reciprocation of the gear blank.

Obviously, in order to form a gear with the machine of this invention, it is necessary to advance the cutting tools radially toward thecenter of the gear blank as the same are fed in and backed off during'the reciprocation of said gear blank. To accomplish'advancementof the tools, a second cam I65 is rotatabl-y-supported atone end ofshaft I44. A follower I61 is rotatably sup.- ported on arm I68 to roll on the periphery of such cam I66 and to pivot arcuatelyabout bolt I69 in said arm I68. Arm I'GBis supported by means of bolt I69, which forms such pivot, to an upwardly directed arm I integral with the bearing housing I45. A' spring I1I, attached to arm I68 and to the projection I4I of carriage I 34, insures that cam I66" and'follower I61 remain constantly engaged. A pawl I12 is secured to arm I68 by means of bolt I13'- andspring I14. Such pawl thus mounted'is'adapted to engage the serrations of ratchet wheel 11 5 'rotatably supported upon shaft I16. This shaft I16 is journaled for rotation upon suitable bearingswithin the bearing housing I11 and I18 formed onthe upwardly-directed arms I10-- and I19 which are integral with projection I4! of carriage I34;

At the opposite end of the-shaft I16, tool advancement cam I80 is rotatably mounted. From the foregoing, it will be appreciated that as cam I66 rotates, it effects arcuate movementof roller I01, causing ratchet I12 to partially rotate ratchet wheel I each time said cam I66 completes one revolution. As ratchet I15 is rotated in this manner, it eif'ectsrotation of cam I80, Cam I80 contacts follower I8'I anchored in adepending position from vertical wedge- I32 which is disposed in a rear portion of head I I5.

Inasmuch as head H5 is held stationary in a down position during the operation of the machine ,it'may be appreciated thatrotation of the cam I against-the follower I8'I willeffect carriage I34" to move downwardly against spring I 83. This independent downward movement of carriage. I34'effects outer cone I30 to move downwardly in the outerretainer ring I84-surrounding tool head H4. Such movement ofthe cone effects the. depending end I64 of feed ring, I163 to enter more deeply into' groove I65 inthe cutting tool, serving'to cause said tool to approach the center of the gear blank without in any way effecting or interfering with the infeed and backoff of such'tools due to the reciprocationof sleeve I3I.

The spring I83 is retained within opening-l85 provided in head I I5by means ofplug186; Such spring I83resiliently urges. camI00 into. contact with follower-I8I at all times, and'the force exerted by said spring against carriage I34"may.b,e varied by turning plug l8dwhichtthreadably engagesopening'I85', either inwardly oroutwardly depending upon the pressure desired;

Adjustment is provided by. shield I31 to control the rate at which the cutting tools are thus advanced. Such shield I01 is held by the slidably movable bolt I 38 positioned in the arcuate' slot I39, provided in a rearwardly-directed ear of arm I10; to be moved to covera desired number of serrations on the ratchet. Then as: pawl I12 moves upwardly,'it is receivedin the first serration open'to it, thereby effecting rotation of the ratchet. Obviously, the sooner pawl I12 enters the serrations on such ratchet, the greater the rotation thereof, and likewise, later engagement produces less rotation, thereby effectively controlling advancement of the tools.

In order to drive the cutting tool infeedand backoff and advancement mechanism just described in timed relationship withreciprocation of'the gear blank I9, driving of such mechanism iseffected-by means of the previously described shaft 84. Such shaft 84 is driven directly from crankshaft 42 in the following manner. At the left end of" the crankshaft 42-, as may be seen in Figure 6, bevel gear I drives bevel gear I9'I secured to shaft I92. for driving the same and bevel gear I93 atthe opposite end-of said shaft. Gear I93, in turn, drives gear I94 which receives the splined end of shaft 84 for driving the same. Such shaft 84 drives the previously described'eccentric 83 and gear I95-splined thereto for'driving bevel gear I96. on shaft I44 which effects the driving of the cutting tool feeding mechanism.

As stated in the foregoing, during this reciprocation'of sleeve I3I and tool advancement, head II5 'is locked in down position. Such locking is accomplished by means of lock bars I91 and I98 which are contained within hydraulic cylinders I99 and 200, respectively, mounted at the rear of such head II 5. In Figure 9, a section'through one of such hydraulic cylinders is shown toillustrate the operating mechanism interiorly of such cylinders. It: will be seen in this figure. that: the lockibar I98 is attached to a piston rod 20 IJWithin such cylinder 200; and-that -piston.rod-20I- is provided'with a piston 202 whichwill be moved inwardly as fluid'is introducedinto chamber 203. Such inward movement effects the lock bar'to move I into a locking position with head II5" for rigidly and positively holding such head 'in a down position. It may also be seen that as fluid is introduced into chamber 204 of such cylinder 200, lock bar I98 will be removed from the looking position permitting the head to moved upwardly at the termination of the forming operation. The operation of lock bar I9! is exactly identical to that of I98 and inasmuch as the operation of each is inter-dependent upon the other, it is to be appreciated that the action of each is simultaneous to effect such locking action of head II5.

In order to accommodate gears of varying diameters, the previously described wedge I 82 may be moved upwardly or downwardly, depending upon the size of the gear to be formed. Movement of such wedge effects a similar movement of carriage I34, as it may be seen by referring to the description of the tool advancement mechanism, cam follower I8I is constantly in engagement with the tool advancement cam I80. If, for example, a gear of relatively small diameter is to be formed with a machine of this invention, it would be necessary to effect the downward movement of carriage I34 by means of vertical Wedge I 82, causing outer cone I30 to move downwardly in outer ring I84. Such downward movement of the outer cone I30 would effect a similar movement of retainer ring I63 for causing depending end I64 of such ring to enter more deeply into groove I65 of cutting tools II3. This adjustment would cause such tools II 3 to move inwardly to effect the cutting of such small gear, without in any way aifecting the infeed, backoff, or advancement of such cutting tool. In a similar manner, if a gear of relatively large size were to be cut, the vertical wedge would be moved upwardly effecting a similar upward movement of carriage I34 by virtue of the force exerted upon the bottom of said carriage by spring I83. Such adjustment would efiect the cutting tools to be removed in an outward manner for cutting,a larger gear.

This vertical adjustment of the vertical wedge I82 is accomplished upon laterally moving wedge 205 in groove 206 provided in head II5 for such wedge 205. Wedge 205 provides inclined surfaces 20'! and 208 which are adapted to slide within groove 209, provided in the vertical wedge I82, as wedge 205 moves in groove 206. much as the Weight of wedge I82 rests upon the upper surface 201 of the wedge 205, a hardened wear plate 2I0 is keyed within groove 209 to prevent undue friction from interfering with the sliding action of said wedge 205.

Such sliding movement of wedge 205 is effected by means of the rotatable feed screw 22I. The feed screw 2 is journaled for rotation upon suitable bearings carried by head I I5 and bracket 2| 2 anchored to such head. A lead nut 2I3 secured to one end of the wedge 205 threadably engages such feed screw 2 and it will be obvious that as such feed screw is rotated, the lead nut will move along the same effecting lateral shifting of the wedge 205. As such wedge 205 shifts laterally, the inclined surfaces 201 and 208 effect a vertical movement of vertical wedge I82 to effect shifting of carriage I34.

Rotation of feed screw 2 is effected upon rotation of the bevel gear 2 I4 by the meshing'bevel gear 2I5 journaled in bearing housing 2I6 for rotation therein. In order to rotate this gear 2| 5, a wrench or other suitable means may be applied to the squared end 2II on shaft 2I8 for rotating the same and with it, bevel gear 2I9 se- Inas- 12 cured thereto. Gear 2I9 meshes bevel gear 220 integrally connected to shaft 22I which is journaled for rotation in bearing housing 222. This shaft is keyed to gear 2I5 and efiects rotation of such gear.

After carriage I34 is adjusted to a predetermined position, vertical wedge I02 may be locked against further movement by means of pin 223 which bears against the surface of said vertical wedge I82. Such pin 223 is slidably positioned within an opening provided therefor in cover 224, which cover is secured to a portion of head II5 for maintaining the vertical wedge I82 in position. A smaller end 225 of pin 223 is secured by means of screw 226 within an opening provided in post 221 which is held in a position perpendicular to vertical wedge I82 by means of shaft 228.

Such shaft 228 is anchored by means of cover 224 to head I I5 and provides at 229 a threaded end to threadably receive the ratchet nut 230. As ratchet nut 230 is turned in one direction, it effects post 221 and thereby pin 223 to move inwardly pressing upon vertical wedge I82 for securely and positively locking the same against movement. Rotation of nut 230 in an opposite direction effects the pressure exerted by pin 223 against the vertical wedge I82 to be relieved, after which such member may be moved to adjust the cutting tool.

This rotation of ratchet nut 230 may be accomplished by handle 23I, the upper end of which receives said nut. Such handle has elongated pin 232 with end 233 thereon adapted to be resiliently urged between serrations 234 of nut 230 by spring 235. The spring 235 encircles pin 232, pressing upon collar 236 on such pin and ear 23! of handle 23'I to bring about this engagement. When end 234 is engaged in this manner, handle 23I may be turned to effect the desired rotation of nut 230. Removing end 234, by moving the pin downwardly, prevents further rotation of ratchet nut 230 until it is again necessary to shift vertical wedge I82.

Inasmuch as the effectiveness of the cutting tools II3 depends upon the sharpness of the cutting edges 238, it will be quite obvious that such cutting surfaces must be sharpened from time to time. It will be appreciated, therefore, that the depth of the cutting tool will be slightly decreased each time the same is sharpened. In order to compensate for this decrease in depth of the cutting tool, an adjustment is provided whereby the entire head assembly II 5 may -b lowered.

It may be seen in Figure 4 that the head II5 rests upon foot 239 provided by base I when the machines is in operating position. Such foot 239 is secured to base I by bolts 240 and upon loosening such bolts may be lowered by means of the following apparatus.

This foot portion 239'provides a, groove 24I in which wedge 242 is slidably positioned. Wedge 242 provides an upper inclined surface 243 and a lower inclined surface 244 adaptedto slide between the wear plates 245 at the top, and 246 at the bottom, which are keyed to the foot portion 239. After bolts 240 are loosened, it will be appreciated that as the wedge member 242 moves laterally in groove 24I, foot portion 239 will shift.

Lateral movement of Wedge 242 is effected by means of feed screw 241 which threadably engages a tapped opening 248 in such wedge. This feed screw is journaled for rotation in bearing block 249 anchored to base I. As such feed screw 24'! is rotated, wedge 252 is effected to slidably move. in groove 2. In order to efiectithiszrotation of the feed screw 241, a conveniently accessible hand wheel 256'is provided at. the opcated in a predeterminedposition, hand screw 254, threadably received by bearing block 249, is

turned inwardly. In this position, the end'of such screw 254 bears against said feed screw 241 rigidly and positively locking against further rotation.

Inasmuch as'lock bars I91 and I98 must beg-in a retracted position when head H5 is brought to a new position by means of foot member 239,, it will ,be obvious that openings 255 and 256-in3lock blocks 25.8 .and 25.9, respectively, for receiving lock pins 1 61 and --I' 98, will be moved downwardly with said head I I5. When so-moved downwardly, such .openings.2;55 and 256 will no longer matelockbars I91 and I98, and adjustment must .be provided-to again bringthelock bars 191 and HIS-into position to mate such openings.

It will be. observed in Figure 9, by again considering only one of the lock bars inasmuch ;as

each is identical, that hydraulic -cylinder'=-'266, is

secured to casing '266which is in surrounding relationshipto sleeve 26I-in which 'loclr bar 1.98 is slidably positioned. The casing 266 is in turn secured to the base portion I of the machine by means ,of-the retainer ring 262. .Upon loosening bolts 263 which hold such retainer ring 262 to base I, :casing 266. may berotated.= Casing ,266 provides at 264 gear teeth adapted to mesh the teethcof Worm 265 which is rotatably supported by shaft 266. Such shaft266 is journaledfor-ro- Y tation in bearing provided in opening 261- in base I and in the bearing housing 268 anchored to such base I. This 'shaft266 provides at 269a squared end which may be engaged by-a wrench or other suitable means for efiecting rotation of said shaft. As the shaft is thus rotated, the worm 265 rotates casing .266 by means of the gear teeth 264 thereon. Casing 266being eccentric to the center of lock bar I98, .effectssuch lock bar 198 to be moved into vertical adjustment withv lock block Rotation of .casing .266, however, moves loci: bar 198 out of lateral adjustment with the lock block .259, and to :provide for this shifting, said lock block.may be moved laterally uponloosem,

ingbolt 216. Whenbolt 216 is loosened, lock block .259may be moved into positionto receive lock ,pin ,1 98 and the bolt again tightened to-hold such lock in the proper-position.

.In asimilar manner, lock bar I91 may be adjusted tomatethe lock block 258 after head 115 has been lowered.

The automatic work cycle maybe initiatedby pressing simultaneously bothv motor start button Y211 and hydraulic start button 212. 'This effects motor v36 to start driving hydraulic pump. 213 which delivers fluid under pressure through line 214 end'port 215 to four-way valve 216. Simultaneously, solenoid 211 on valve 216,,is energized shifting the piston in such valve sogasxto :permit ;the:nressurized::.fi.uid 5,110. flow zoutqof n0rtm2 18 through. line 2'19wto:.:line 236. Fromj-linelliflfl, the] .fluid entersrpassagewayw :2 81 which, delivers itto chamber 12.8provided:inzzhy rauliccylinder .122. ;As;-fl,ui'd -underrpressureirenters chamber ;t28,yhe.ad I:-I 5:.mo;vesdownwardly. At the. same timer) fluid :line 2.80 :is delivered o port 282 bfrwork :clamp cylinders 12.8.3. .-F!romrport 2.8 :suchriiuid enters :chamber :284. :of v{the cylinder, .causingpiston 2,85 andirod 286 tormove; inwardly f o r efiecting gear. blank I9 to bezrigidlyzandposirtively clamped in position in workholder I1. :In- .asmilch as athe hydraulic circuitris closed; the downwardrmovement; :of piston I26 gin cylinder I22 effects fluid in chamber I29 to be exhausted therefrom i through passageway :281. and, line 288 "toimetzas and port 2290 on gfour way valve 216. "This; fluid then-:leaves :said ;valve byway of port 29 lczand :line: 2.9.2. for return. .to ereservoiri. 293. ewise,' -fluid rinchamberw294 of cylinder: 12:83 ispexhaustedgby way ;of .port' 5295 to line 296 cior tetrurn'to reservoir 29.3.

Wben head .H 5 reaches .the'li'mit .ofzitsi downward .travel, .pin 294, which may be seen in Fig- ;ure 2 and-whieh is only ,diagrannnaticallyci-llustrated in-Figurelii, contacts limit switch.- 295, ;energizing-. solenoid 2296 --on four-way. valve .291. Thus, actuated, valve .291-shiits, permitting fluid .under ;pressure girom line ,298 to enter pQIt V299 and 'flow. through said valve leaving .the, same by way ,oiport "366 to enter-lin,e:;36l,. Line-36,6 delivers asuch fluid to port, 362 I of the :sequence valve .363. which git leaves by'way of port 364cm- .tering line 3.65, which --delivers the :same to line 366 and then to 361 ports and 368 of hydraulic -,cy1inders.266-and.369. From port 361 such fluid renters. .chamber 263, while that from port 368 entersvchamber H6 in the respective hydraulic .cylindersefiecting lock bars I91 and 198 to move ..draulic,,pressure builds up in sequence valve 363,

into .locking position. Following this, the hywhichzopens at a pre-set pressure and allows the fluid :to--flow outof port 3II- on said valve into ,.line-.3;I.2 to port 3I3 of the clutch control cylinder 3I4. This fluid passes through saidport 313 into chamber-3L5 of the clutch control cylinder caus- ..ing=.piston 3IB therein to move clutchg32 into an :engagedposition. When clutch 32 becomes en- ..gaged,-,crank 36 is set into motion by the previlines 319 and .32l'lrfor port 32I on sequence valve 5 .322.

v i ng through-,port 3'23 and enteringline 3.24, for

This fluid passes through said valve, leavr,eturn.to -portl325 :of valve 291'to be exhausted byrway. of port 326 and line 321. Likewise, fluid is exhausted from chamber 328 .of cylinder 314 v by way of port 329 andline 336 to port 33I .of

.valve..32 2 for return.

..As@the clutch becomes ,fully engaged, lever 3I1 actuated by piston .3I6contacts limit-switch 3I8,

,deeenergizing solenoid 211 on four-wayvalve 216 and solenoid 296 on,-four-way valve- 291. This aotionjs provided to guarantee positive positioning ofthe four-way valves 2-16 and 291, and to remoyejthemirom'the circuit after their purpose has been accomplished.

In the ioregoingythe. oscillation of ram guide housingtl' due to the action of the variable spiral guide means has been described. In connection '-with thisloscillationof theram guide housing 9,

the function of rotatable shaft=98 'has also been -=described. As. shaft 98 rotates -in'the described 

